Washington — For months now, it has been clear that Republicans will try to make the 2014 midterm elections all about "Obamacare" as they push to win majority control of the Senate. This week, Democrats will counter in earnest with their election theme. Starting Monday, they will turn to issues of income inequality in a bid not only to rouse their base, but also to win support from middle-class Americans who worry that only the rich are getting richer.

Senate majority leader Harry Reid (D) will try on Monday to clear a legislative hurdle to allow a vote on extending unemployment insurance for 1.3 million long-term jobless Americans whose benefits expired Dec. 28. Look, too, for Senate Democrats to push for a higher federal minimum wage. Democrats are making both efforts against the historic backdrop of President Lyndon Johnson’s “war on poverty,” launched 50 years ago this week in his State of the Union message.

President Obama, meanwhile, will carry the torch further on Jan. 28, when he’ll use his State of the Union address to echo a pre-Christmas speech in which he declared that income inequality and declining social mobility are “the defining challenge of our time.”

It is a political strategy that carries some risks. Some Americans are already wary of Mr. Obama's aims, wondering whether he lied to them – falsely telling them they could keep health insurance plans they liked – in order to win passage of legislation that makes insurance widely available to the poor. Moreover, the inequality issue has the potential to expose a fault line among Democrats, with liberals such as Sen. Elizabeth Warren of Massachusetts pushing the party to go much further down the path of federal entitlements and benefits than many others are comfortable going.

So far, the party appears to be stopping short of an Occupy Wall Street revival. Extending long-term unemployment benefits and raising the minimum wage both have majority public support, according to polls. Those polls also reveal a broad unease about the widening income inequality.

But with the Republican base fired up for what is shaping up to be a low-turnout midterm election, the clearest target for Democrats' new push is likely Democratic voters themselves. The question, then, becomes: How far should Democrats go?

“Democrats must be careful in how they frame the issue” of inequality, says John Pitney Jr., a congressional expert at Claremont McKenna College in California. “If voters think that the idea is to redistribute wealth from the middle class to the poor, Democrats will lose badly.”

Since the botched rollout of the Affordable Care Act on Oct. 1, the problem that most concerns Americans has been “dissatisfaction with the government,” not the economy generally, which has fallen into second place, followed by health care, according to Gallup. The gap between the rich and poor is farther down the list: Only 2 percent rank it as the country's top problem. Therein lies the balancing act for Democrats trying to steer public interest away from the problems of Obamacare to an issue – helping the downtrodden – where the party holds an historic advantage.

For now, Democrats appear to be opting for caution. About 2 in 3 Americans want Congress to boost the minimum wage, according to a Washington Post-ABC poll released last month. Obama supports a Senate bill to raise the minimum wage to $10.10 an hour, up from $7.25 an hour, where it has stood since 2009.

The attempt is to help the working poor. Whether you contrast the wage growth of the lowest-income earners with the highest in America, or look at the percentage of overall wealth controlled by the richest, economic inequality has intensified. Meanwhile, the poverty rate – roughly 15 percent for the past three years – is up from a low of 11 percent in 1973.

The Washington Post-ABC poll shows a majority of Americans concerned about this trend: 57 percent of the public says Congress should pursue policies aimed at rebalancing an economy that’s out of whack.

Likewise, 55 percent of Americans support maintaining unemployment insurance for the long-term jobless, according to a recent Hart Research poll. While affecting only a slice of the workforce, such a move resonates with many Americans who fear they may lose their jobs, and worry about what will happen to them if they do. “That’s why this issue could work for Democrats,” says Mr. Pitney.

Democrats are also carefully choosing their rhetoric. Some have invoked the popular Pope Francis, who recently warned that income inequality will lead to “an economy of exclusion.” Some are citing economist Mark Zandi, former adviser to Sen. John McCain (R) of Arizona, who defends benefits for the long-term unemployed as a boost to economic growth. They note that the nonpartisan Congressional Budget Office finds that failure to renew unemployment benefits will cost more than 200,000 jobs. And they are highlighting individual cases to put human faces on their arguments.

In this way, Democrats can hope to turn the tables on Republicans. Going back to the Great Depression and the New Deal, Democrats have made defending the downtrodden their trademark – and that issue can be a challenge for Republicans, who sometimes sound out-of-touch. A prime example: 2012 presidential candidate Mitt Romney’s comment about the 47 percent of Americans who are “dependent on government” and “unwilling to take personal responsibility and care for their lives.” It reinforced his plutocrat image in the 2012 campaign, which Obama went on to win handily even in a bad economy.

Some Republicans are trying to counter the Democrats on income inequality. Sen. Mike Lee of Utah (who helped lead the fight to shut down the government) and Rep. Paul Ryan of Wisconsin are using softer language, promoting private-sector solutions that emphasize volunteerism and charity, and touting tax cuts as a way to spur growth. “The perception that the GOP does not care about people” is “a major deficiency,” a Republican National Committee review of the 2012 campaign found. The review suggested that the party “be the champion of those who seek to climb the economic ladder.”

“Washington has gummed up the works,” Representative Ryan told an Iowa crowd in November, according to the Washington Post. “It’s made it harder for people to get ahead, and the idea of upward mobility, of equal opportunity, is slipping farther and farther away from people who haven’t seen it for generations.” For months, Ryan – Mr. Romney’s running mate, who may well seek the presidency in 2016 – has been meeting with neighborhood leaders in cities nationwide. He’s expected soon to lay out a plan to combat poverty.

Republican lawmakers may well block an extension of jobless benefits if it’s not paid for by offsetting savings, and they generally oppose an increase to the minimum wage as a disincentive to hire. But even if Democrats in Congress don't come away with a legislative win on these points, their efforts to defending the disadvantaged will play well with the Democratic base.

Democrats are “outlining an agenda” not only for this year, but also for future years, says congressional historian Julian Zelizer at Princeton University. “A lot of Democrats feel the last two years have been consumed with health care … and the deficit,” he explains. “Until you shift the debate, you’re not going to be able to get in a position where you can push for legislation like the [higher] minimum wage. And this is the right time because the Republicans are in a moment of division” over whether to obstruct or to compromise.

Democrats, too, have their internal arguments. One has broken out between the left wing, led by consumer crusader and freshman Senator Warren, and the Democratic centrists, many of whom come from the Clinton camp. Warren is barricading entitlement programs against cuts and even advocates increasing Social Security benefits; centrists counter that the only way to invest in the infrastructure, education, and green energy that will make America competitive is to curtail the entitlement spending that will explode as baby boomers retire in their social-safety hammocks.

The split, for now, is mostly an inside-the-Beltway dustup. Neither Republicans nor Democrats are moving toward a fiscal “grand bargain” that would trade cuts to Medicare and Social Security for tax increases. Inequality issues such as extending jobless benefits and raising the minimum wage are ones that progressives and centrists alike can support.

As can a majority of the American public. That explains why, from a political standpoint, inequality is in.